וַיִּגֹּ֥ף יְהוָ֖ה אֶת־הָעָ֑ם עַ֚ל אֲשֶׁ֣ר עָשׂ֣וּ אֶת־הָעֵ֔גֶל אֲשֶׁ֥ר עָשָׂ֖ה אַהֲרֹֽן׃ (ס)
And the LORD smote the people, because they made the calf, which Aaron made.
Read kabbalistic (mystical) interpretation of Exodus 32:35: and classical mystical sources.